Switch doesn't work with numeric comparison cases

Question

Here is my code.

$value = 0;
switch($value) {
      case ( $value <= 25 ):
            $CompScore = \'low\';
            break;
      case ($value > 25         


        

Answer 1

The value you pass into a switch statement is basically what the switch statement looks for an evaluated match for, going from top to bottom down the list of cases until it finds one it is equal to (loose comparison), e.g. true == true.

In your example, your comparisons are evaluated as booleans (true or false) - your variable $value is set to zero, which is equal to false, but not identical (strict comparison) to false. For example:

(0 == false)    // true
(0 === false)   // false
(1 == false)    // false
(1 === false)   // false
(1 == true)     // true
(1 === true)    // false
(true === true) // true

So by using a boolean true as your switch value, you can do this to have numeric comparison inside the statement, where each comparison will evaluate to either true or false to match/not match the original true value (boolean - boolean comparison).

switch(true) {
       case ($value <= 25):                 // true
             $CompScore = 'low';
             break;
       case ($value > 25 && $value <= 50 ): // false
             $CompScore = 'fair';
             break;
       case ($value > 50 && $value <= 75 ): // false
             $CompScore = 'good';
             break;
       case ($value >75 ):                  // false
             $CompScore = 'excellent';
             break;
       default:                             // if you removed the first case
             $CompScore = 'low';            // this default case would be used
             break;                         
 }